Luminous printing

ABSTRACT

A method and a device are disclosed for luminous printing of an original image using fluorescent ink or other fluorescent display pigments. In some embodiments, the original image is separated into multiple layers, including at least a brightness layer and an inverse brightness (or darkness) layer, by applying extracted brightness data and inverse brightness data, to the original image, respectively. Each of the layers is associated with a set of corresponding printing channels. The sets of printing channels are applied by a printing device to print the original image on a print medium, such as paper, mylar, fabric, and other print surfaces. Multiple visual effects may be realized using the aforementioned process, including fluorescent images that are only visible under UV (Ultra Violet) or black light, images with high-fidelity colors under daylight and dark conditions, and shadow effects such as depth illusion.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. Nonprovisional patentapplication Ser. No. 12/956,234, filed Nov. 30, 2010, soon to be issuedas U.S. Pat. No. 9,066,051, which claims the benefit of the filing dateunder 35 USC 119(e) of the filing date of U.S. Provisional ApplicationSer. No. 61/310,710, filed Mar. 5, 2010, the contents of which areincorporated herein by reference.

TECHNICAL FIELD

This application relates generally to a printing process. Morespecifically, this application relates to luminous printing processusing different image layers and corresponding sets of color channels.

SUMMARY

In aspects of present disclosure, a method of printing images isdisclosed including separating the original image into multiple layers,associating a different set of channels with each of the multiplelayers, where the different set of channels are configured to be used togenerate a printed image that looks substantially equivalent underdaylight conditions and Ultra Violate (UV) black light conditions. Themethod further includes printing each of the multiple layers using thecorresponding set of channels.

In further aspects of the present disclosure, a method of printingimages is disclosed including separating the original image intomultiple layers, associating a different set of channels with each ofthe multiple layers, wherein the different set of channels areconfigured to be used to generate a printed image that is substantiallyinvisible under normal daylight and visible in substantially full andaccurate color under Ultra Violate (UV) black light. The method furtherincludes printing each of the multiple layers using the correspondingset of channels.

In still further aspects of the present disclosure, a printing system isdisclosed including a printing press configured to print images, and acomputing device coupled with the printing press. The computing deviceis configured to digitally separate an original image into multiplelayers, associate a different set of channels with each of the multiplelayers, wherein the different sets of channels are configured to be usedto generate a printed image that looks substantially equivalent underdaylight conditions and Ultra Violate (UV) black light conditions. Thecomputing device is configured to print each of the multiple layersusing the corresponding set of channels.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings, when considered in connection with the followingdescription, are presented for the purpose of facilitating anunderstanding of the subject matter sought to be protected.

FIG. 1A is a diagram of an example system for printing images on aprinting device;

FIG. 1B is a diagram of example components of a computing device;

FIG. 1C is an example diagram of a Red-Green-Blue (RGB) color space;

FIG. 1D is an example diagram of the RGB additive color model;

FIG. 2A is an example diagram of a Cyan-Magenta-Yellow-Black (CMYK)color space;

FIG. 2B is an example diagram of the CMYK subtractive color model;

FIGS. 3 a-3 f show examples of invariant luminosity under daylight withrespect to different fluorescent and non-fluorescent yellow (actualcolor not shown) color proportions;

FIGS. 4 a-4 d show examples of invariant luminosity under daylight withrespect to different yellow fluorescent and white color proportions;

FIGS. 5 a-5 f show examples of variable luminosity under dark lightingconditions with respect to different fluorescent and non-fluorescentyellow (actual color not shown) color proportions;

FIGS. 6 a-6 d show examples of invariant luminosity under dark lightingconditions with respect to different fluorescent and white colorproportions;

FIG. 7 is a flow diagram of an example process of luminous printingresulting in a printed image visible in daylight and under black light;

FIG. 8 is a flow diagram of an example process of luminous printingresulting in a printed image invisible in daylight and visible underblack light;

FIG. 9 is a flow diagram of an example process of creation of a palletof fluorescent colors using base fluorescent colors;

FIG. 10 is a flow diagram of an example process of creation of illusionof depth using fluorescent and non-fluorescent colors; and

FIG. 11 is a flow diagram of an example process of creation of a printedwhite color that is invisible in daylight and visible as white colorunder black light.

DETAILED DESCRIPTION

While the present disclosure is described with reference to severalillustrative embodiments described herein, it should be clear that thepresent disclosure should not be limited to such embodiments. Therefore,the description of the embodiments provided herein is illustrative ofthe present disclosure and should not limit the scope of the disclosureas claimed. In addition, while following description references printingon physical surfaces such as paper, fabric, and plastic, it will beappreciated that the disclosure may be used for other image processingand display applications such as televisions, computer monitors,projectors, and the like.

Briefly described, a method and a device are disclosed for luminousprinting of an original image using fluorescent ink or other fluorescentdisplay pigments. In some embodiments, the original image is separatedinto multiple layers, including at least a brightness layer and aninverse brightness (or darkness) layer, by applying extracted brightnessdata and inverse brightness data, to the original image, respectively.Each of the layers is associated with a set of corresponding printingchannels. The sets of printing channels are applied by a printing deviceto print the original image on a print medium, such as paper, mylar,fabric, and other print surfaces. Multiple visual effects may berealized using the aforementioned process, including fluorescent imagesthat are only visible under UV (Ultra Violet) or black light, imageswith high-fidelity colors under daylight and dark conditions, and shadoweffects such as depth illusion.

Printing is a ubiquitous part of the modern life. Color printing ofimages is now widely available to all users, professional and amateuralike, via modern printing devices, such as ink jet printers, laserprinters, and the like. Color printing is especially important incommercial advertisements, printed matter and periodicals, commercialsigns and displays, and entertainment, among others. Commercial printjobs are generally processed via a printing press for quality and costreasons.

To effectively work with colors, many color systems have been devised,each for particular types of applications. For example, Red-Green-Blue(RGB), Cyan-Magenta-Yellow-Black (CMYK), and many other variations, arecolor spaces that are in common use. Color spaces are closely related tocolor models, which are mathematical models that related differentcolors to each other for easy reference and analysis. A color space isgenerally defined in terms of a few base colors (such as red, green,blue in RGB) and all other colors in that space are defined in terms ofthe various combinations of the intensities of the base colors. Forexample, red and green generate yellow.

Color models may be additive, like RGB, or subtractive, like CMYK. Inadditive color spaces, a base color that is emitted causes a resultingcolor to be generated, while in subtractive color spaces, a base colorthat subtracts other reflected color from a white background, which is amixture of all colors. CMYK is often used in printing processes. Colorspaces and models are further described below with reference to FIGS. 1Cand 1D.

Half-toning or quarter-toning of light and/or colored pigments reducesthe light and/or color density on a projection and/or print surface onwhich light is shone and/or color is printed by some percentage,respectively. That is, half-toning reduces color saturation on a printsurface. Tiny dots of each primary (or basic) color may be printed in apattern small enough that human eye perceives as a solid color. Forexample, magenta printed with a 20% halftone on white paper generates apink color because the magenta dots and the white space between the dotsare collectively perceived as lighter and/or less saturated than puremagenta. Without half-toning, the three primary process colors may beprinted only as solid colors, limiting the resulting combinations toonly three additional colors. Utilizing half-toning, a substantiallycontinuous range of colors may be generated.

Colors may be treated as signals because a color is basically specifiedby a particular frequency and/or wavelength of light waves. As such,signal processing concepts and techniques are generally applicable tocolor images and color processing. Colors also have certaincharacteristics, such as lightness and brightness, which help in theunderstanding color processing. Lightness of a color is the perceptionof color that ranges from black, through gray, to white, under the samelighting conditions and regardless of the hue. The physical counterpartof lightness is reflectance, the permanent property of a surface thatdetermines what portion of incident light the surface reflects. Forexample, surfaces that appear white reflect about 90% of the lightstriking them. Black surfaces reflect about 3%. In short, lightness isperceived reflectance.

Brightness is the perception of color that ranges from dim to bright,under the same lighting conditions and regardless of the hue. Likelightness, brightness is a perceptual term. The physical counterpart ofbrightness is luminance—that is, the absolute intensity of lightreflected in the direction of the observer's eye by a surface. In short,if lightness is perceived reflectance, brightness is perceivedluminance. The reflectance of an object is a relatively permanentproperty, whereas its luminance is transient.

FIG. 1A is a diagram of an example system for printing images on aprinting device. In one embodiment, the example printing system includesa computing device 102, sending commands 104 and data 106 to a printingdevice 108 to print images on a print surface 110. In some embodiments,computing device 102 is a general purpose computer or a dedicatedterminal for use with the printing device. The image to be printed istypically preprocessed on computing device 102 and is then transmittedin the form of digital or analog data 106 to printing device 108.Depending on the interface of the printing device, commands 104 may betransmitted to printing device 108 to process received data 106 beforeprinting on print media such as paper, fabric, mylar, and the like.Commands 104 vary greatly depending on the printing device interface andtypically include commands about various print media to use, orientationof the printed image, quality of print, and the like. Those skilled inthe art will appreciate that other embodiments of printing systems arepossible without departing from the spirit of the present disclosures.For example, data and/or commands may be directly loaded onto theprinting device via a keypad, a data tape, a disc, or other computerreadable media, without a computer interface.

FIG. 1B is a diagram of example components of a computing device. Insome embodiments, computing device 102 of FIG. 1A is substantially thesame as computing device 120, which may include a Central ProcessingUnit (CPU) 122, coupled via a control and/or data bus 126 to otherfunctional units such as memory 124, display interface 134, NetworkInterface Card (NIC) 136, Input/Output (I/O) 138, and mass storagedevice 132. Memory 124 may include an Operating System (OS) 130,application software 128, and other types of computer-executablesoftware components, such as device drivers for peripheral devices likeprinting and mass storage devices. Those skilled in the art willappreciate that computing device 120 may include fewer, more, different,more integrated, and/or functionally separated components than theillustrative components shown in FIG. 1B. Computing device 120 may beused to execute application programs such as image processingapplications, color processing applications, and printing applications.

FIG. 1C is an example diagram of a Red-Green-Blue (RGB) color space. Thebase colors are generally shown as overlapping color sets 152 for red,154 for green, and 156 for blue. The overlaps between the base colorsets show different colors resulting from the combination of the basecolors. For example, yellow 158, cyan 160, and pink 162. A full spectrumof colors may be generated by the base colors based on the intensity ofeach base color in the combination. In various embodiments, the basecolors may take any intensity value in a predetermined range such as 1to 255, represented in digital computers by an 8-bit (one byte)quantity. Depending on the particular value of the base colors RGB in aparticular combination, a different color is generated. For example, forthe set {R, G, B}={186, 22, 50} (where: R=186, G=22, B=50), one color isgenerated, while for the set {R, G, B}={15, 85, 204}, a different coloris generated. Colors in a color image may be represented and/or encodedusing RGB. The RGB values form a 3-dimensional space as furtherdescribed below with respect to FIG. 1D.

FIG. 1D is an example diagram of the RGB additive color model. RGB maybe modeled by a Cartesian system in which each of the base colors R, G,and B, constitutes one of the dimensions, 170, 172, and 174,respectively. The origin of this system where {R, G, B}={0, 0, 0}corresponds to the black color and {R, G, B}={255, 255, 255} correspondsto the white color, if the range of values for the base colors isdefined as 1 to 255. RGB color model is additive because starting withno color (black), the base colors are added to zero colors to generateother colors. This is in contrast to subtractive models where startingwith all colors (white), the base colors are subtracted from the mix ofall colors to generate other colors.

FIG. 2A is an example diagram of a Cyan-Magenta-Yellow-Black (CMYK)color space. CMYK color space 200 has four base colors that whencombined with different intensities generate different colors. In asimilar manner to RGB, the base colors of CMYK, Cyan 202, magenta 204,yellow 202, and black 208 are combined in different proportions togenerate different colors.

FIG. 2B is an example diagram of the CMYK subtractive color model. In asubtractive color model, starting with all colors (white), the basecolors are subtracted from the mix of all colors to generate othercolors. A cylindrical coordinate system may be used to model the CMYKcolor space. Each point in a cylindrical coordinate system is specifiedusing three coordinates consisting of one angle around the cylinder 242,the distance from the center of the cylinder 244, and the length of thecylinder 246. In Hue-Saturation-Value (HSV), angle 242 may be used torepresent the hue “dimension”, while distance from the center 244 andlength of the cylinder 246 are used to represent saturation and value,respectively. In other similar representation, the value may be replacedwith lightness (HSL) or intensity (HSI).

Those skilled in the art will appreciate that there are many other colorspaces, such as YUV, YCbCr, YPbPr, and the like, that are used indifferent applications like television and video color systems.

In FIGS. 3 a-3 f through FIGS. 6 a-6 d, the horizontal axis of thehistograms are luminosity and the vertical axis are number of imagepixels at the corresponding luminosity, with the luminosity starting atlow values towards the left end of the diagrams and increasing to highervalues towards the right end. Each sub-figure, for example, a, b, c, andthe like, shows a particular proportion of a fluorescent color and anon-fluorescent color, in a progressive manner, along with thecorresponding histograms. For example sub-FIG. 3 a shows 100%fluorescent yellow color and 0% non-fluorescent yellow color, whilesub-FIG. 3 b shows 80% fluorescent yellow color and 20% non-fluorescentyellow color.

FIGS. 3 a-3 f show examples of invariant luminosity under daylight withrespect to different fluorescent and non-fluorescent yellow (actualcolor not shown) color proportions. FIG. 3 a shows an examplefluorescent yellow color as 100% of the color mixture andnon-fluorescent yellow color as 0% of the color mixture. As FIG. 3 istraversed from sub-FIG. 3 a to sub-FIG. 3 f, the invariance ofluminosity of pixels becomes clear. That is, the same luminosityhistogram is obtained regardless of the proportion of the mixed colorsunder the given lighting conditions.

FIGS. 4 a-4 d show examples of invariant luminosity under daylight withrespect to different yellow fluorescent and white color proportions. AsFIG. 4 is traversed from sub-FIG. 4 a to sub-FIG. 4 d, the invariance ofluminosity of pixels becomes clear. That is, the same luminosityhistogram is obtained regardless of the proportion of the mixed colorsunder the given lighting conditions.

FIGS. 5 a-5 f show examples of variable luminosity under dark lightingconditions with respect to different fluorescent and non-fluorescentyellow (actual color not shown) color proportions. In contrast to FIGS.3 and 4, As FIG. 5 is traversed from sub-FIG. 5 a to sub-FIG. 5 f, thevariation of luminosity of pixels becomes clear. That is, differentluminosity histograms are obtained as the proportion of the mixed colorschanges under the given lighting conditions. More specifically, insub-FIG. 5 a, luminosity histogram is towards the right end (moreluminous) of the diagram, progressively moving towards the left (lessluminous) as sub-FIGS. 5 b to 5 f are traversed.

FIGS. 6 a-6 d show examples of invariant luminosity under dark lightingconditions with respect to different fluorescent and white colorproportions. As FIG. 6 is traversed from sub-FIG. 6 a to sub-FIG. 6 d,the invariance of luminosity of pixels becomes clear. That is, the sameluminosity histogram is obtained regardless of the proportion of themixed colors under the given lighting conditions. However, the standarddeviation of the histogram is reduced in this traversal, showing lessvariation of luminosity when 100% of fluorescent color is maintainedwhile increasing the proportion of white.

FIG. 7 is a flow diagram of an example process of luminous printingresulting in a printed image visible in daylight and under black light.To create an image, which looks substantially equivalent under normaldaylight and under 345 to 400 nm black light, Process 700 may be used.The process proceeds to block 710 where a color format is selected forthe representation of an original digitized image to be printed. Forexample, a CMYK format may be selected for the original image forfurther processing. The process proceeds to block 720.

At block 720, brightness data are extracted from the original image andused as further described below. In various embodiments, a broad processis utilized to separate the original image into multiple layers andassociating a different set of color channels with each of the multiplelayers. During printing, each of the multiple layers is printed usingthe corresponding set of color channels.

In various embodiments, the multiple layers include at least two layers,a first layer, Brightness layer (high brightness value), of the originalimage, and a second layer, a Darkness layer (low brightness value), ofthe original image. The resulting data are printed on a printing pressto create a printed image with the desired characteristics, as furtherdescribed below.

In various embodiments, depending on the format used a multi-colorprinting press is used. For example, with CMYK format, an 8-colorprinting press may be used with C, M, Y, K, Cf, Mf, Yf, Wi colors, whereC, M, Y, and K are the CMYK format colors; Cf, Mf, Yf are fluorescentversions of the same colors; and Wi is White Invisible fluorescentcolor. The Darkness layer pixels are associated with and may be printedusing C, M, Y, K colored ink, and the Brightness layer is associatedwith and may be printed using the Cf, Mf, Yf, Wi colored ink. Theprocess proceeds to block 730.

At block 730, in various embodiments, the Brightness layer is generatedby extracting the brightness information of the original image. Theextracted data generally results in a grayscale image which describesthe relative brightness of every pixel in the original image. In variousembodiments, the extracted brightness data may be used as a mask to beapplied to the original image to generate the brightness layer. Uponapplication of the brightness mask to the original image, a first set ofchannels is obtained including the colors to be used for printing thebrightness layer. The first set of color channels may be assigned as:C=Cf, M=Mf, Y=Yf and K is deleted to be replaced later, as describedbelow. The process proceeds to block 740.

At block 740, in various embodiments, an inverse of the brightness dataextracted in block 720 is applied to the C, M, Y channels of theoriginal image, resulting in the isolation of a darkness of the originalimage as the darkness layer associated with a second set of channels forprinting the Darkness layer. The second set of color channels for thislayer is assigned as: C=C, M=M, Y=Y and K=K, where the black channel (K)remains the same as the original image. The process proceeds to block750.

At block 750, white information of the original image is determined toenable the printing of the image with Wi color. Lightness information ofthe image is extracted resulting in a grayscale image, which describesthe relative lightness of every pixel. With this technique, thelightest, for example, “quarter tone,” values of the original image areisolated. The resulting data is applied to the Wi channel. In variousembodiments, the above procedures constitute the preprocessing of theoriginal image prior to printing. The overall result of the aboveprocedures is the creation of two layers, Brightness and Darknesslayers, and eight color channels—C, M, Y, K, and Cf, Mf, Yf, Wi—dividedinto two sets of channels, one each for the printing of the Brightnessand Darkness layers, respectively. The process proceeds to block 760.

At block 760, the data included in the Brightness and Darkness layers istransmitted to the printer, for example, via a computing device, to beprinted using the two corresponding sets of color channels. In variousembodiments, the image is printed in one pass, while in otherembodiments, the image may be printed in multiple passes, for example,to perform additional filtering operations on the image to be printed.

The process terminates at block 770.

FIG. 8 is a flow diagram of an example process of luminous printingresulting in a printed image invisible in daylight and visible underblack light. More specifically, to create an image, which issubstantially invisible under normal daylight and visible insubstantially full and accurate color under 345 to 400 nm black light,process 800 may be used. The process proceeds to block 810 where a colorformat is selected for the representation of an original digitized imageto be printed. For example, a CMYK format may be selected for theoriginal image for further processing. The process proceeds to block820.

At block 820, brightness data are extracted from the original image andused as further described below. In various embodiments, a broadtwo-step process is utilized. In the first step a first layer,Brightness layer (high brightness value), of the original image iscreated while in the second step a second layer, Darkness layer (lowbrightness value), of the original image is created. The resulting dataare printed on a printing press to create a printed image with thedesired characteristics.

In various embodiments, an 8 color printing press is used, with C, M, Y,K, Ci, Mi, Yi, Wi colors, where C, M, Y, and K are the CMYK formatcolors; Ci, Mi, Yi are Invisible fluorescent versions of the samecolors; and Wi is White Invisible fluorescent color. The Darkness layerpixels may be printed using C, M, Y, K colored ink, and the Brightnesslayer may be printed using the Ci, Mi, Yi, Wi colored ink. The processproceeds to block 830.

At block 830, in various embodiments, the Brightness layer is generatedby extracting the brightness information of the original image. Theextracted data generally results in a grayscale image which describesthe relative brightness of every pixel in the original image. Theextracted brightness data is applied to the original image as a mask ona pixel-by-pixel basis. In various embodiments, the brightness data maybe used as a mask to be applied to the original image. Upon applicationof the brightness mask to the original image, a first set of channels isobtained including the colors to be used for printing the brightnesslayer. The first set of color channels may be assigned as: C=Ci, M=Mi,Y=Yi and K is deleted to be replaced later, as described below. Theprocess proceeds to block 840.

At block 840, in various embodiments, an inverse of the brightness dataextracted in block 820 is applied to the C, M, Y channels of theoriginal image, resulting in the isolation of a darkness of the originalimage as a second set of channels for printing the Darkness layer. Thesecond set of color channels for this layer is assigned as: C=C, M=M,Y=Y and K=K, where the black channel (K) remains the same as theoriginal image. The process proceeds to block 850.

At block 850, white information of the original image is determined toenable the printing of the image with Wi color. Lightness information ofthe image is extracted resulting in a grayscale image, which describesthe relative lightness of every pixel. With this technique, thelightest, for example, “quarter tone,” values of the original image areisolated. The resulting data is applied to the Wi channel. In variousembodiments, the above procedures constitute the preprocessing of theoriginal image prior to printing. The overall result of the aboveprocedures is the creation of two layers, Brightness and Darknesslayers, and eight color channels—C, M, Y, K, and Ci, Mi, Yi, Wi—dividedinto two sets of channels, one each for the printing of the Darkness andthe Brightness layers, respectively. Ki (Black Invisible) may be used asone of the color channels. Ki absorbs black light when applied over afluorescent substrate and will appear black under black light. Theprocess proceeds to block 860.

At block 860, the data included in the Brightness and Darkness layers istransmitted to the printer, for example, via a computing device, to beprinted using the two corresponding sets of color channels. In variousembodiments, the image is printed in one pass, while in otherembodiments, the image may printed in multiple passes, for example, toperform additional filtering operations on the image to be printed.

The process terminates at block 870.

Invisible fluorescent ink are “clear” inks that when printed aresubstantially invisible under normal daylight but appear insubstantially full and accurate color under UV black light.

FIG. 9 is a flow diagram of an example process of creation of a palletof fluorescent colors using base fluorescent colors. Process 900proceeds to block 910 where a set of standard fluorescent inks and/orcolors is prepared for use. The process proceeds to block 920.

At block 920, the standard fluorescent base colors are mixed inpredetermined proportions to create other non-base fluorescent colors.This way color separation may be effected by digitally mixingfluorescent colors to create the full pallet of fluorescent colors. Theuse of standard fluorescent colors results in printed image beingvisible in a color accurate manner under both normal daylight and UVblack light. Using invisible or clear fluorescent inks, the printedimage will substantially not be visible under normal daylight but willsubstantially appear in full color under UV black-light.

For example, given the base colors—fluorescent cyan, fluorescent yellowand fluorescent magenta, 100% fluorescent yellow and 100% fluorescentmagenta may be mixed to create fluorescent red. Similarly, 100%fluorescent yellow and 25% fluorescent magenta may be digitally mixed tocreate fluorescent orange.

The process proceeds to block 930 and terminates.

FIG. 10 is a flow diagram of an example process of creation of illusionof depth using fluorescent and non-fluorescent colors. Process 1000proceeds to block 1010, where non-fluorescent ink is intermixed withfluorescent ink during printing to create the illusion of depth in theprinted image. To create lesser degrees of fluorescence, non-fluorescentinks may be intermixed with fluorescent inks. The addition ofnon-fluorescent cyan, magenta, yellow and black, to the extent to whichthey are added to the fluorescent ink, creates an effect of comparativedarkness under UV black light. For example, a subject image may beprinted in fluorescent ink, and any shadows in the subject image may beprinted in non-fluorescent color to create the illusion of depth.

The process proceeds to block 1020 and terminates.

FIG. 11 is a flow diagram of an example process of creation of a printedwhite color that is invisible in daylight and visible as white colorunder black light. Process 1100 proceeds to block 1110, wherefluorescent inks are mixed with fluorescent white during printing tocreate a printed image that is substantially invisible in normaldaylight and is white under UV black light. To create lesser degrees offluorescence, it is also possible to intermix a single UV lightinhibiting clear ink, which substantially completely absorbs UV lightfrequency and substantially negates the propensity of fluorescent ink tofluoresce.

To create a fluorescent highlight effect, fluorescent inks may be mixedwith fluorescent white. This mixture creates a clear ink, which isinvisible under normal daylight and is white under UV black-light.

The process proceeds to block 1120 and terminates.

It will be understood that each block of the flowchart illustration, andcombinations of blocks in the flowchart illustration, can be implementedby computer program instructions. These program instructions may beprovided to a processor to produce a machine, such that theinstructions, which execute on the processor, create means forimplementing the actions specified in the flowchart block or blocks. Thecomputer program instructions may be executed by a processor to cause aseries of operational steps to be performed by the processor to producea computer implemented process such that the instructions, which executeon the processor to provide steps for implementing the actions specifiedin the flowchart block or blocks. The computer program instructions mayalso cause at least some of the operational steps shown in the blocks ofthe flowchart to be performed in parallel. Moreover, some of the stepsmay also be performed across more than one processor, such as mightarise in a multi-processor computer system. In addition, one or moreblocks or combinations of blocks in the flowchart illustration may alsobe performed concurrently with other blocks or combinations of blocks,or even in a different sequence than illustrated without departing fromthe scope or spirit of the invention.

Accordingly, blocks of the flowchart illustration support combinationsof means for performing the specified actions, combinations of steps forperforming the specified actions and program instruction means forperforming the specified actions. It will also be understood that eachblock of the flowchart illustration, and combinations of blocks in theflowchart illustration, can be implemented by special purposehardware-based systems which perform the specified actions or steps, orcombinations of special purpose hardware and computer instructions.

Changes can be made to the claimed invention in light of the aboveDetailed Description. While the above description details certainembodiments of the invention and describes the best mode contemplated,no matter how detailed the above appears in text, the claimed inventioncan be practiced in many ways. Details of the system may varyconsiderably in its implementation details, while still beingencompassed by the claimed invention disclosed herein.

Particular terminology used when describing certain features or aspectsof the invention should not be taken to imply that the terminology isbeing redefined herein to be restricted to any specific characteristics,features, or aspects of the invention with which that terminology isassociated. In general, the terms used in the following claims shouldnot be construed to limit the claimed invention to the specificembodiments disclosed in the specification, unless the above DetailedDescription section explicitly defines such terms. Accordingly, theactual scope of the claimed invention encompasses not only the disclosedembodiments, but also all equivalent ways of practicing or implementingthe claimed invention.

The above specification, examples, and data provide a completedescription of the manufacture and use of the composition of theinvention. Since many embodiments of the invention can be made withoutdeparting from the spirit and scope of the invention, the inventionresides in the claims hereinafter appended. It is further understoodthat this disclosure is not limited to the disclosed embodiments, but isintended to cover various arrangements included within the spirit andscope of the broadest interpretation so as to encompass all suchmodifications and equivalent arrangements.

What is claimed is:
 1. A method of printing images, the methodcomprising: separating the original image into multiple layers;associating a different set of channels with each of the multiplelayers, wherein the different set of channels are configured to be usedto generate a printed image that looks substantially equivalent underdaylight conditions and Ultra Violate (UV) black light conditions; andprinting each of the multiple layers using the corresponding set ofchannels.
 2. The method of claim 1, wherein separating the originalimage into multiple layers comprises separating the original image intotwo layers including a brightness layer and a darkness layer.
 3. Themethod of claim 2, wherein separating the original image into two layerscomprises: extracting brightness information from the original image;applying the brightness information to the original image to generate abrightness layer and determine a first set of channels associated withthe brightness layer; determining inverse brightness information; andapplying the inverse brightness information to the original image togenerate a darkness layer and a second set of channels associated withthe darkness layer.
 4. The method of claim 3, wherein printing each ofthe multiple layers using the corresponding set of channels comprisesprinting the brightness layer using the first set of channels andprinting the darkness layer using the second set of channels.
 5. Themethod of claim 1, further comprising selecting a format to representthe original image.
 6. The method of claim 5, wherein the formatcomprises CMYK (Cyan, Magenta, Yellow, black).
 7. The method of claim 1,further comprising extracting lightness information from the originalimage.
 8. The method of claim 1, wherein the different set of channelscomprise fluorescent and non-fluorescent color channels.
 9. The methodof claim 8, wherein one of the different set of channels comprises cyan,magenta, yellow and black colors, and another one of the different setof channels comprises fluorescent cyan, fluorescent magenta, fluorescentyellow, and invisible white.
 10. A method of printing images, the methodcomprising: separating the original image into multiple layers;associating a different set of channels with each of the multiplelayers, wherein the different set of channels are configured to be usedto generate a printed image that is substantially invisible under normaldaylight and visible in substantially full and accurate color underUltra Violate (UV) black light; and printing each of the multiple layersusing the corresponding set of channels.
 11. The method of claim 10,wherein separating the original image into multiple layers comprisesseparating the original image into two layers including a brightnesslayer and a darkness layer.
 12. The method of claim 11, whereinseparating the original image into two layers comprises: extractingbrightness information from the original image; applying the brightnessinformation to the original image to generate a brightness layer anddetermine a first set of channels associated with the brightness layer;determining inverse brightness information; and applying the inversebrightness information to the original image to generate a darknesslayer and a second set of channels associated with the darkness layer.13. The method of claim 12, wherein printing each of the multiple layersusing the corresponding set of channels comprises printing thebrightness layer using the first set of channels and printing thedarkness layer using the second set of channels.
 14. The method of claim13, wherein the format comprises CMYK (Cyan, Magenta, Yellow, black).15. The method of claim 14, wherein the first set of channels comprisesinvisible fluorescent cyan, invisible fluorescent magenta, invisiblefluorescent yellow and invisible white colors, and the second set ofchannels comprises cyan, magenta, yellow, and black.
 16. A printingsystem comprising: a printing press configured to print images; and acomputing device coupled with the printing press, wherein the computingdevice is configured to digitally separate an original image intomultiple layers, associate a different set of channels with each of themultiple layers, wherein the different sets of channels are configuredto be used to generate a printed image that looks substantiallyequivalent under daylight conditions and Ultra Violate (UV) black lightconditions, and wherein computing device is configured to print each ofthe multiple layers using the corresponding set of channels.
 17. Theprinting system of claim 16, wherein a format of the original imagecomprises CMYK (Cyan, Magenta, Yellow, black).
 18. The printing systemof claim 17, wherein the multiple layers comprise two layers including abrightness layer and a darkness layer.
 19. The printing system of claim18, wherein the brightness layer is associated with a first set ofchannels comprising fluorescent cyan, fluorescent magenta, fluorescentyellow and invisible white colors, and the darkness layer is associatedwith a second set of channels comprising cyan, magenta, yellow, andblack colors.
 20. The printing system of claim 18, wherein thebrightness layer is generated by applying a brightness mask to theoriginal image and the darkness layer is generated by applying aninverse of the brightness mask to the original image.